1.1 本试验方法包括在恒定温度条件下，通过无内胎轮胎结构的空气扩散导致的充气压力损失率的测定。测试在静态条件下进行，即非旋转、非负载轮胎。 1.2 以国际单位制表示的数值应视为标准。括号中给出的值仅供参考。 1.3 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的用户有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 1.4 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认标准化原则制定的。 ====意义和用途====== 5.1 充气压力保持力是轮胎性能的一个重要特性，因为充气不足会对轮胎滚动阻力、操纵性、结构完整性和胎面寿命产生不利影响。 5.2 该试验方法有助于研究和开发评估轮胎组件配方和几何形状对充气压力保持力的影响。静态条件下的压力损失率测试是可行的，因为: 5.2.1 正常使用的轮胎主要处于静止状态，并且 5.2.2 在正常间歇性道路服务中，各种轮胎的相对空气扩散率将与静态相对速率相关，达到一级近似值。在动态弯曲下，不同轮胎的相对空气扩散率可能与静态测试时不太相同，但据信差异很小。 5.3 本试验方法的结果不适用于推断在恶劣工况下的轮胎充气保持力，例如严重转弯或碰撞，这可能会导致轮胎轮辋密封处的显著空气损失。

1.1 This test method covers the determination of the rate of inflation pressure loss resulting from air diffusion through the structures of tubeless tires under constant temperature conditions. The testing is done under static conditions, that is, nonrotating, nonloaded tires. 1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee. ====== Significance And Use ====== 5.1 Inflation pressure retention is an important property of tire performance because underinflation can adversely affect tire rolling resistance, handling, structural integrity, and tread life. 5.2 This test method is useful for research and development evaluation of the effects of tire component formulations and geometry on inflation pressure retention. Testing for rate of pressure loss under static conditions is practical because of the following: 5.2.1 Tires in normal use are predominantly at rest, and 5.2.2 Relative air diffusion rates of various tires in normal intermittent road service will correlate with static relative rates, to a first approximation. The relative air diffusion rates of different tires may not be quite the same under dynamic flexing as when tested statically, but the difference is believed to be small. 5.3 The results from this test method are not suitable for inferring tire inflation retention under severe service conditions, such as heavy cornering or impacts, that might cause significant air loss at the tire-rim seal.